Added documentation

README.md

@@ -37,9 +37,61 @@ dependencies:
     branch: master
 ```
 
-## Status
+## Routes
 
-Basic `get`, `put`, `post`, `patch`, `delete` and `head` routes can be matched, and request parameters can be obtained.
+In Kemal, a route is an HTTP method paired with a URL-matching pattern. Each route is associated with a block:
+
+```ruby
+  get '/' do
+  .. show something ..
+  end
+
+  post '/' do
+  .. create something ..
+  end
+
+  put '/' do
+  .. replace something ..
+  end
+
+  patch '/' do
+  .. modify something ..
+  end
+
+  delete '/' do
+  .. annihilate something ..
+  end  
+```
+
+## Context
+
+Accessing the request context (query params, body, headers e.g) is super easy. You can use the context returned from the block:
+
+```ruby
+  # Matches /hello/kemal
+  get '/hello/:name' do |ctx|
+    name = ctx.params["name"]
+    "Hello back to #{name}"
+  end
+
+  # Matches /resize?width=200&height=200
+  get '/resize' do |ctx|
+    width = ctx.params["width"]
+    height = ctx.params["height"]
+  end
+```
+
+## Content Type
+Kemal uses *text/html* as the default content type. You can change it via the context.
+
+```ruby
+  # Set the content as application/json and return JSON
+  get '/user.json' do |ctx|
+    kemal = {name: 'Kemal', language: 'Crystal'}
+    ctx.set_content_type "application/json"
+    kemal.to_json
+  end
+```
 
 ## Thanks